<script language="javascript" type="text/javascript">
  function preview() {
  bdhtml = window.document.body.innerHTML;
  sprnstr = "<!--startprint-->";
  eprnstr = "<!--endprint-->";
  prnhtml = bdhtml.substr(bdhtml.indexOf(sprnstr) + 17);
  prnhtml = prnhtml.substring(0, prnhtml.indexOf(eprnstr));
  window.document.body.innerHTML = prnhtml;
  window.print();
  }
</script>

<!--startprint-->
  <div id="note" class="utList">
  <asp:GridView ID="gvList" runat="server" AutoGenerateColumns="False" Width="100%"
  DataKeyNames="QuantityName" BorderWidth="4px" BorderColor="White" GridLines="Vertical"
  OnRowCommand="gvList_RowCommand" OnRowDataBound="gvList_RowDataBound">
  <RowStyle CssClass="no1" />
  <Columns>
…………………………
  </tr>
  </table>
  </EmptyDataTemplate>
  <HeaderStyle CssClass="title" />
  <AlternatingRowStyle CssClass="no2" />
  </asp:GridView>
  </div>
  <!--endprint-->
打印页面只显示这几个字母： "; eprnstr = "
是什么情况？